Water absorption of paper and board can affect dimensions and mechanical properties, This highly affects the quality of papers and boards. The produced paper should be targeted to resist water or moisture. A number of different methods of testing the absorbency of paper and board are available but the method known as ‘Klemm’ is commonly used.
BS 6504 describes a method of determining the absorption of water by paper and board using a closed vessel to provide a saturated atmosphere. This method requires the test to be carried out in a closed chamber.
The method provides better accuracy than the open vessel method in BS 2916. BS 6504 is applicable to all paper and board with medium or high-water absorbency where the wetting of the material can be detected visually.
Note: BS 6504 is not recommended for materials having a capillary rise of less than 5 mm.
BS 6504 on testing water absorbency of paper and board is useful for:
Papers may be destroyed or unreadable if the paper changes their form by absorbing water. For unsized papers such as blotting papers and other papers having relatively high-water absorbency the Klemm method for determining water absorbency is used.
BS 6504 provides you with the Klemm method to determine the amount of water absorbed into the surface by a sized paper, paperboard, and corrugated fibreboard paper or paperboard sample in a set period of time.
BS 6504 guides you with the test procedure, preparation of test pieces, sampling and conditioning of test samples. Following BS 6504 guidelines help you to produce the paper which is suitable for the manufacturing of water-resistant corrugated packaging materials.